Saccharomyces cerevisiae genomic clones that encode calmodulin-binding proteins were isolated by screening a lambda gt11 expression library using 125I-labeled calmodulin as probe. Among the cloned yeast genes, we found two closely related genes (CMP1 and CMP2) that encode proteins homologous to the catalytic subunit of phosphoprotein phosphatase. The presumed CMP1 protein (62,999 Da) and CMP2 protein (68,496 Da) contain a 23 amino acid sequence very similar to those identified as calmodulin-binding sites in many calmodulin-regulated proteins. The yeast genes encode proteins especially homologous to the catalytic subunit of mammalian phosphoprotein phosphatase type 2B (calcineurin). The products of the CMP1 and CMP2 genes were identified by immunoblot analysis of cell extracts as proteins of 62,000 and 64,000 Da, respectively. Gene disruption experiments demonstrated that elimination of either or both of these genes had no effect on cell viability, indicating that these genes are not essential for normal cell growth.

The kinetic parameters (kcat/Km) and the cleaved-bond distributions for the hydrolysis of linear maltooligosaccharides Gn (3 less than or equal to n less than or equal to 9) by Saccharomycopsis alpha-amylase (Sfamy) secreted from Saccharomyces cerevisiae were determined at pH 5.25 and 25 degrees C. The subsite affinities of Sfamy were also evaluated from these data. The subsite structure of Sfamy is characteristic of the active site of an endo-cleavage type enzyme, consisting of internal repulsive sites with the catalytic residues and external attractive sites. Moreover, the pKa values of the catalytic residues were calculated from the pH dependence plot of the kinetic parameter (kcat/Km). The amino acid residues which contribute to the subsite affinities and the catalytic activity of Sfamy are proposed and compared with those of Taka-amylase A.

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Fundamental experiments are conducted to confirm the calcium reactivity with titanium oxide in the molten calcium chloride. The TiO 2 samples placed in the molten salt could be reduced without any electron supply to TiO 2 . In the close vicinity of cathode, TiO 2 could be successfully reduced to -Ti with 1600 mass ppm oxygen. However, the strong stirring of the melt disturbed the calcium distribution near the cathode and the reduction was incomplete. These findings supported the proposed mechanism that Ca deposited on the cathode and it dissolved immediately into the molten salt. The parasite reactions consumed the dissolved Ca quickly, and they suppressed the effective reduction and subsequent deoxidation.

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